Its not the amount of levels so much as the quality and use. Big playerworlds are meant to promote exploring. The sad part though is that they aren't built for exploring. Nothing too adventurous about most gmaps full of trees and such. And yes, players will clump together, but thats the glory of your main town. Its why you spent so long on it.
So here's what I'm getting at. When you spend time on your levels, make it because its been scaled to that. That your world is more than just an island. That it took the player three to five minutes to get from town to town because he hasn't gotten a horse yet. Or hasn't established some kind of inter-city travel.
And as always, Make little areas where people can sit. All my fondest memories of NPulse are on the little tables next to that cave. Babylon's main area. Valikorlia's main cities.
So my suggestion for Armageddon, Big gmaps are fabulous. But how about section off an area you can complete in a foreseeable time. Make some...event, so that you can rope off the exits. Like a carnival or maybe some kind of police lock-down. And develop quality instead of rushed quantity.

Really hope for good things on Armageddon.